I respectfully disagree. As my post points out, the internal air flow impedance was almost certainly reduced from the RS1 to the RS10/20, and the fan isolation may have been improved, but the net power removal (in watts) appears to be the same. In a number of products I design, air cooling is required. To simplify things (within 15%), a liter per second of airflow is required to keep the delta T at one degree C for a heat load of one watt. The fan in the RS1 is reasonably well isolated, but it is a cheap POS with readily discernible cogging and imbalance when hand held. JVC could have and almost certainly did spend more and got more when they selected the RS10/20 fan and determined its operating voltage, and this was after a fair degree of consumer complaints about the RS1. There is a very simple metric for fan model and voltage adequacy, and that is the air inlet to outlet delta T. If, as I expect, a fan with better aerodynamics, cogging, and balance was chosen for the RS-10/20, and an owner would identify the make/model and voltages, I could easily find the applied voltage on that fan (assuming that it has the same frame size and thickness) that would match the RS-1's inlet to outlet delta T, and hence provide equivalent lamp cooling.
I reiterate my request: if anyone, from Cine4home (who first identified the RS1 fan) to individual owners otherwise interested in the RS10/20's internals can determine the make, model, and ideally voltage(s) of the main fan, would you please post it? Thank you.
Oh, and as to the suggested "simple fix" (just turn the volume up), the films that we screen include (I know that this may be unbelievable) silent passages, in which the DP's work shines, and there aren't any car chases to mask projector noise.